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	<title>数学对象</title>
	<script type="text/javascript">
	res= Math.abs('-10');
	//alert(typeof(res));
	//
	/*res=Math.round(1.5);

	res=Math.ceil(1.00002);

	res=Math.floor(3.99);

	res=Math.random()*100;
	alert(res);*/
	now=new Date();
	document.write(now.getHours());

	document.write(Math.round(now.getTime()/1000));
	document.write('<br>');

	date51=new Date("2017-05-01");
	document.write(Math.round(date51.getTime()/1000))







	</script>
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<body>
	
</body>
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